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Material Measurement Laboratory

Biosystems and Biomaterials Division

FCSC Working Group 4

A figure with two panels. Left panel shows the activities of WG4-ILS1 physical titer, WG4-ILS2 infectious titer, and WG4-ILS3 purity, as funneling into the result of measurement assurance for gene delivery systems and potential generation of standard methods, reference materials or reference data. Right panel shows the activities of WG4-ILS1 that will be distributed to labs through sharing contributed materials for measurements of genome titer, capsid titer, particle concentration, and other methods.

WG4 Interlaboratory Study Activities.  A. Multiple interlaboratory studies are planned to support gene delivery system measurement assurance.  B. WG4-ILS1 study activities are focused on physical titer measurements.

Gene Delivery Systems

Working Group 4 (WG4) efforts are focused on identifying and minimizing the sources of variability in assays of gene delivery system assays. Consensus-based methods, reference materials, and reference data are expected to be made available to the community from these efforts.  Activities in progress include:

  1. An interlaboratory study on physical titer measurement of gene delivery systems WG4 is actively planning its first interlaboratory study (WG4-ILS1) on physical titer measurements of gene delivery systems including genomic titer, capsid titer, particle concentration, and other novel and/or orthogonal physical titer methods.
    1. Contributed materials - AAV2, AAV8, AAV9, lentivirus, adenovirus, and extracellular vesicles, have been contributed by Consortium members for interlaboratory comparison.
    2. Particle concentration measurements - NIST has used contributed instruments to perform measurements including mass photometry, nanoparticle tracking analysis, resistive pulse sensing, and nanoparticle flow cytometry.  Additional particle concentration measurements are ongoing.
    3. SOPs complete - WG4 has developed standardized protocols dPCR genome titer measurements of AAV and LVV.  These protocols include best practices and control materials that provide measurement assurance during genomic material processing and analysis.
    4. Interlaboratory samples shipped - NIST is currently sending study samples to Consortium members for analysis.  AAV and LVV materials are being sent and analyzed first.  AdV, LNP, and EV samples will follow.
  2. International documentary standards participation Working group members are participating in the development of international documentary standards through ISO to harmonize analytical methods for gene delivery systems.  Standards completed and under active development with WG4 participation include:

Return to NIST Flow Cytometry Standards Consortium main page

Biotechnology, Bioeconomy, Biological data, Biomanufacturing, Biometrology, Cell measurements, Gene delivery systems, Health, Cell and gene therapy, Clinical diagnostics, Cancer, Precision medicine, Regenerative medicine and advanced therapy, Flow cytometry, Metrology, Amount of substance, Standards and Reference materials

Contacts

Working Group 4 Technical Leads

Consortium Principal Investigator

Created November 29, 2024, Updated September 15, 2026
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